[no_mind_golfer]

Did you know....

if you tug on the string of a simple pendulum at just the right time you can inject kinetic energy and increase the amplitude of oscillation?

http://www.millersville.edu/~physics....the.month/34/

In that experiment the student is using a loudspeaker which tugs up and down on the pendulum string at just the right frequency in order to increase the amplitude. Its called parametric acceleration.

The same principle can be used to extract energy. When the phasing is such that it extracts energy, its sometimes called: active vibration control or active vibration damping. What's this have to do with golf in general and this thread in particular?

Its the same.

When the club is releasing it is like a pendulum, the club is swinging about a point at the wrists. While we cannot shorten the length of the club shaft during the swing we can apply more centripetal acceleration than is needed to keep the club rotating. We can tug "UP" at just the right time thereby injecting kinetic energy to the club head. When done in the final stage of the downswing this is effectively the same thing as "reducing the hand path radius". In 2002 a Japanese scientist wrote a paper proving the amazing efficacy of this technique to increase club head speed called: Parametric Acceleration in Golf Swing.

http://www3.interscience.wiley.com/j...TRY=1&SRETRY=0
http://sciencelinks.jp/j-east/articl...06A1001780.php


All long hitters do it. They may not know they're doing it ... but all long hitters inject that final dose of energy by "pulling up" at the end of the downswing. Some even end up on their toes as a result like Bubba.

One interesting bit of data reported by Nesbit is that a wide range of players have almost exactly the same hand speed profile (bottom set of curves on link below notice its not slowing as others suggest either but that's another issue)

http://www.jssm.org/vol4/n4/17/F4.htm

Their hand velocity profiles are nearly identical yet clearly some swings are much more effective than the others. What's the difference? Its the path their hand follow reducing radius vs. non-reducing (or even increasing) radius... its pulling up at at the last second vs. not pulling up..

Its all in the hands folks... use your body to make your hands go where they've got to go.